College and grades- help please?

have you ever made goals for yourself when you first entered high school? you have all these dreams to go to all these good colleges. the summer before 9th grade you plan to be rank 1 and be the best. however school starts and you're distracted by things. i ruined my freshman year and last semester of this year (sophmore)- like reall badly. i got a D's and C's along with A's and B's during freshman year and last semester. im trying so hard to maintain all a's but currently i have all a's and b's. i really want to go to uga, emory, or oxford college at emory university. what do i do? please help me? any tips on how to succeed and how to get in these colleges so that for this semester and junior and senior year i can work my off trying to do extremely good and get in these amazing colleges? please, please help me. i scewed up in thebeginning and i want my feet on the ground this time. please help!